2016-12-27 08:10:47 -08:00

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.. -*- mode: rst -*-
=====================
The full Pygments API
=====================
This page describes the Pygments API.
High-level API
==============
.. module:: pygments
Functions from the :mod:`pygments` module:
.. function:: lex(code, lexer)
Lex `code` with the `lexer` (must be a `Lexer` instance)
and return an iterable of tokens. Currently, this only calls
`lexer.get_tokens()`.
.. function:: format(tokens, formatter, outfile=None)
Format a token stream (iterable of tokens) `tokens` with the
`formatter` (must be a `Formatter` instance). The result is
written to `outfile`, or if that is ``None``, returned as a
string.
.. function:: highlight(code, lexer, formatter, outfile=None)
This is the most high-level highlighting function.
It combines `lex` and `format` in one function.
.. module:: pygments.lexers
Functions from :mod:`pygments.lexers`:
.. function:: get_lexer_by_name(alias, **options)
Return an instance of a `Lexer` subclass that has `alias` in its
aliases list. The lexer is given the `options` at its
instantiation.
Will raise :exc:`pygments.util.ClassNotFound` if no lexer with that alias is
found.
.. function:: get_lexer_for_filename(fn, **options)
Return a `Lexer` subclass instance that has a filename pattern
matching `fn`. The lexer is given the `options` at its
instantiation.
Will raise :exc:`pygments.util.ClassNotFound` if no lexer for that filename
is found.
.. function:: get_lexer_for_mimetype(mime, **options)
Return a `Lexer` subclass instance that has `mime` in its mimetype
list. The lexer is given the `options` at its instantiation.
Will raise :exc:`pygments.util.ClassNotFound` if not lexer for that mimetype
is found.
.. function:: guess_lexer(text, **options)
Return a `Lexer` subclass instance that's guessed from the text in
`text`. For that, the :meth:`.analyse_text()` method of every known lexer
class is called with the text as argument, and the lexer which returned the
highest value will be instantiated and returned.
:exc:`pygments.util.ClassNotFound` is raised if no lexer thinks it can
handle the content.
.. function:: guess_lexer_for_filename(filename, text, **options)
As :func:`guess_lexer()`, but only lexers which have a pattern in `filenames`
or `alias_filenames` that matches `filename` are taken into consideration.
:exc:`pygments.util.ClassNotFound` is raised if no lexer thinks it can
handle the content.
.. function:: get_all_lexers()
Return an iterable over all registered lexers, yielding tuples in the
format::
(longname, tuple of aliases, tuple of filename patterns, tuple of mimetypes)
.. versionadded:: 0.6
.. module:: pygments.formatters
Functions from :mod:`pygments.formatters`:
.. function:: get_formatter_by_name(alias, **options)
Return an instance of a :class:`.Formatter` subclass that has `alias` in its
aliases list. The formatter is given the `options` at its instantiation.
Will raise :exc:`pygments.util.ClassNotFound` if no formatter with that
alias is found.
.. function:: get_formatter_for_filename(fn, **options)
Return a :class:`.Formatter` subclass instance that has a filename pattern
matching `fn`. The formatter is given the `options` at its instantiation.
Will raise :exc:`pygments.util.ClassNotFound` if no formatter for that filename
is found.
.. module:: pygments.styles
Functions from :mod:`pygments.styles`:
.. function:: get_style_by_name(name)
Return a style class by its short name. The names of the builtin styles
are listed in :data:`pygments.styles.STYLE_MAP`.
Will raise :exc:`pygments.util.ClassNotFound` if no style of that name is
found.
.. function:: get_all_styles()
Return an iterable over all registered styles, yielding their names.
.. versionadded:: 0.6
.. module:: pygments.lexer
Lexers
======
The base lexer class from which all lexers are derived is:
.. class:: Lexer(**options)
The constructor takes a \*\*keywords dictionary of options.
Every subclass must first process its own options and then call
the `Lexer` constructor, since it processes the `stripnl`,
`stripall` and `tabsize` options.
An example looks like this:
.. sourcecode:: python
def __init__(self, **options):
self.compress = options.get('compress', '')
Lexer.__init__(self, **options)
As these options must all be specifiable as strings (due to the
command line usage), there are various utility functions
available to help with that, see `Option processing`_.
.. method:: get_tokens(text)
This method is the basic interface of a lexer. It is called by
the `highlight()` function. It must process the text and return an
iterable of ``(tokentype, value)`` pairs from `text`.
Normally, you don't need to override this method. The default
implementation processes the `stripnl`, `stripall` and `tabsize`
options and then yields all tokens from `get_tokens_unprocessed()`,
with the ``index`` dropped.
.. method:: get_tokens_unprocessed(text)
This method should process the text and return an iterable of
``(index, tokentype, value)`` tuples where ``index`` is the starting
position of the token within the input text.
This method must be overridden by subclasses.
.. staticmethod:: analyse_text(text)
A static method which is called for lexer guessing. It should analyse
the text and return a float in the range from ``0.0`` to ``1.0``.
If it returns ``0.0``, the lexer will not be selected as the most
probable one, if it returns ``1.0``, it will be selected immediately.
.. note:: You don't have to add ``@staticmethod`` to the definition of
this method, this will be taken care of by the Lexer's metaclass.
For a list of known tokens have a look at the :doc:`tokens` page.
A lexer also can have the following attributes (in fact, they are mandatory
except `alias_filenames`) that are used by the builtin lookup mechanism.
.. attribute:: name
Full name for the lexer, in human-readable form.
.. attribute:: aliases
A list of short, unique identifiers that can be used to lookup
the lexer from a list, e.g. using `get_lexer_by_name()`.
.. attribute:: filenames
A list of `fnmatch` patterns that match filenames which contain
content for this lexer. The patterns in this list should be unique among
all lexers.
.. attribute:: alias_filenames
A list of `fnmatch` patterns that match filenames which may or may not
contain content for this lexer. This list is used by the
:func:`.guess_lexer_for_filename()` function, to determine which lexers
are then included in guessing the correct one. That means that
e.g. every lexer for HTML and a template language should include
``\*.html`` in this list.
.. attribute:: mimetypes
A list of MIME types for content that can be lexed with this
lexer.
.. module:: pygments.formatter
Formatters
==========
A formatter is derived from this class:
.. class:: Formatter(**options)
As with lexers, this constructor processes options and then must call the
base class :meth:`__init__`.
The :class:`Formatter` class recognizes the options `style`, `full` and
`title`. It is up to the formatter class whether it uses them.
.. method:: get_style_defs(arg='')
This method must return statements or declarations suitable to define
the current style for subsequent highlighted text (e.g. CSS classes
in the `HTMLFormatter`).
The optional argument `arg` can be used to modify the generation and
is formatter dependent (it is standardized because it can be given on
the command line).
This method is called by the ``-S`` :doc:`command-line option <cmdline>`,
the `arg` is then given by the ``-a`` option.
.. method:: format(tokensource, outfile)
This method must format the tokens from the `tokensource` iterable and
write the formatted version to the file object `outfile`.
Formatter options can control how exactly the tokens are converted.
.. versionadded:: 0.7
A formatter must have the following attributes that are used by the
builtin lookup mechanism.
.. attribute:: name
Full name for the formatter, in human-readable form.
.. attribute:: aliases
A list of short, unique identifiers that can be used to lookup
the formatter from a list, e.g. using :func:`.get_formatter_by_name()`.
.. attribute:: filenames
A list of :mod:`fnmatch` patterns that match filenames for which this
formatter can produce output. The patterns in this list should be unique
among all formatters.
.. module:: pygments.util
Option processing
=================
The :mod:`pygments.util` module has some utility functions usable for option
processing:
.. exception:: OptionError
This exception will be raised by all option processing functions if
the type or value of the argument is not correct.
.. function:: get_bool_opt(options, optname, default=None)
Interpret the key `optname` from the dictionary `options` as a boolean and
return it. Return `default` if `optname` is not in `options`.
The valid string values for ``True`` are ``1``, ``yes``, ``true`` and
``on``, the ones for ``False`` are ``0``, ``no``, ``false`` and ``off``
(matched case-insensitively).
.. function:: get_int_opt(options, optname, default=None)
As :func:`get_bool_opt`, but interpret the value as an integer.
.. function:: get_list_opt(options, optname, default=None)
If the key `optname` from the dictionary `options` is a string,
split it at whitespace and return it. If it is already a list
or a tuple, it is returned as a list.
.. function:: get_choice_opt(options, optname, allowed, default=None)
If the key `optname` from the dictionary is not in the sequence
`allowed`, raise an error, otherwise return it.
.. versionadded:: 0.8